Calenduloside E from B. animalis B960 enhances glibenclamide efficacy and alleviates drug-induced side effects via the IRS1/PI3K/AKT pathway in T2D

Glibenclamide (GLIB), a type 2 diabetes (T2D) treatment, has long-term safety concerns. Probiotic–drug coadministration, an emerging adjunctive approach for treating metabolic diseases, improves therapeutic outcomes and ameliorates side effects. Here, Bifidobacterium animalis B960 was selected from 71 probiotic strains by high-performance liquid chromatography (HPLC) and in vitro cell assays; it effectively maintained GLIB integrity and ameliorated insulin resistance. In vivo, combined B960+GLIB therapy significantly reduced blood glucose levels, prevented weight gain, improved intestinal homoeostasis and increased beneficial metabolite levels. Moreover, B960 significantly mitigated GLIB-induced side effects, particularly hepatotoxicity and inflammation. B960 activated a 9-enzyme cascade involving IolS and EpsJ, biotransforming oleanolic acid into Calenduloside E, which synergized with GLIB by activating the IRS1/PI3K/AKT signaling pathway; ultimately, this process upregulated insulin effectors (Irs1, Pik3r1, Akt1, and Slc2a4), suppressed gluconeogenic regulators (Gsk3b, Foxo1, and Pck1) and increased insulin sensitivity and glucose utilization. Proof-of-concept studies with insulin-resistant models and a human-relevant gut–liver organ-on-a-chip platform demonstrated targeted insulin sensitization without compromised GLIB pharmacokinetics. This work offers a therapeutic strategy for type 2 diabetes with enhanced efficacy and reduced toxicity.